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Question
Let R be the relation in the set N given by R = {(a, b) : a = b – 2, b > 6}. Choose the correct answer.
Options
(2, 4) ∈ R
(3, 8) ∈ R
(6, 8) ∈ R
(8, 7) ∈ R
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Solution
(6, 8) ∈ R
Explanation:
R = {(a, b) : a = b – 2, b > 6}
Here, since b > 6, hence (2, 4) ∉ R and
3 ≠ 8 – 2, ∴ (3, 8) ∉ R and
8 ≠ 7 – 2, ∴ (8, 7) ∉ R
Now for (6, 8), 8 > 6 and 6 = 8 – 2
∴ (6, 8) ∈ R ≠ R
Hence, option (6, 8) ∈ R is correct.
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